When he returned to Brazil in 1894, Miller brought two footballs and a set of Hampshire FA rules in his suitcase.[4] Miller was instrumental in setting up the football team of the São Paulo Athletic Club (SPAC) and the Liga Paulista, the first football league in Brazil. With him as striker SPAC won the first three championships in 1902, 1903 and 1904.

By 1906, Miller was playing in goal and as such participated in SPAC's heaviest defeat, 9-1 to Sport Club Internacional of São Paulo (not to be confused with Sport Club Internacional). After the result SPAC resigned from the league as did Miller from its directorate.[2]SPAC eventually came back in 1907, even winning the 1911 title, and continued disputing the Campeonato Paulista until 1912, when it retired from official competitions.

In January 1906, he married the renowned pianist Antonietta Rudge; the union produced two children, Carlos (1907) and Helena (1909). The late 1920s saw the couple split with Antonietta moving in with the poet Menotti.

In 1939 on perhaps his last return to England, he was nearly killed in the first IRA bombing on the mainland; his daughter stopped to window shop just seconds before the bomb went off on the steps to the nearby underground station.[2]

He continued to play cricket and golf in later life. He died on 30 June 1953 in São Paulo, and is buried in the protestant cemetery there.